01
Traditional Data Collection Requires Decisions in the Field
With conventional survey data collection, crews typically determine which features and locations need to be measured.
The crew collects the required information and returns to the office. This approach works extremely well when the project's needs are clearly defined.
The challenge comes when those needs change. An engineer may realize another area needs to be included. A contractor may ask for information that was not part of the original request. A designer may need an elevation between previously collected points. When that information was never measured, another site visit may be necessary.
- Ground elevations
- Breaklines
- Structures
- Curbs
- Roads
- Drainage features
- Utilities
- Building corners
- Existing improvements
- Other project-specific points
02
LiDAR Captures More of the Site the First Time
LiDAR can reduce that risk by collecting dense measurements across a much larger portion of the visible environment.
Instead of returning with only selected points, the project team may return with a detailed point cloud containing information across the site.
That means a question that arises later can sometimes be answered from the existing dataset.
- Additional ground elevations
- Slope conditions
- Stockpile dimensions
- Existing structures
- Road surfaces
- Grading conditions
- Site clearances
- Surface changes
- Areas not originally considered important
03
Mobilization Costs Add Up Quickly
The cost of returning to a site includes more than the time spent taking the additional measurement.
A repeat visit can involve crew travel time, vehicle expenses, equipment mobilization, scheduling delays, site access coordination, safety requirements, and lost time on other projects.
For remote projects, those costs can become significant. A jobsite located several hours from the office may require most of a day simply to collect a small amount of missing information.
- Crew travel time
- Vehicle expenses
- Equipment mobilization
- Scheduling delays
- Site access coordination
- Safety requirements
- Lost time on other projects
04
Remote Projects Benefit Even More
The farther away a project is, the more valuable comprehensive data collection becomes.
Survey and engineering firms frequently work across large geographic areas. Contractors may operate in rural locations. Mining, utility, infrastructure, and land development projects may be located far from major population centers.
In those situations, collecting a more complete dataset during the first mobilization can provide insurance against future questions. The goal is not to collect unnecessary information. It is to capture enough of the site that the dataset remains useful as the project evolves.
05
Projects Change After Data Collection
Another reason repeat trips occur is that project requirements change.
The original request might involve a topographic surface. Later, the engineer may want information from another portion of the property. The contractor might need quantity calculations. The owner may want documentation of an existing condition. The project team could decide to evaluate an alternative design.
A dense LiDAR dataset can create flexibility. Information collected for one purpose may sometimes support additional analysis without another complete field effort.
06
A Digital Snapshot of the Site
LiDAR also creates something that becomes impossible to reproduce later.
A detailed record of what the site looked like at a specific point in time. Construction sites change. Stockpiles move. Excavations expand. Buildings are demolished. Utilities are installed. Grades are modified.
Once those changes occur, the original conditions may no longer exist. A LiDAR scan creates a digital snapshot that can be referenced later. That can provide value beyond the immediate deliverable.
07
Pre-Construction Data Can Be Particularly Valuable
Collecting LiDAR before construction begins can create a baseline dataset.
That information may later be compared against grading progress, excavation, new structures, site improvements, finished surfaces, and as-built conditions.
Without good documentation of the original site, answering questions about what changed can be difficult. Pre-construction LiDAR provides a detailed reference that remains available even after the physical site has changed.
- Grading progress
- Excavation
- New structures
- Site improvements
- Finished surfaces
- As-built conditions
08
LiDAR Does Not Eliminate Every Return Trip
There are still situations where another site visit will be necessary.
A feature may have been obstructed. Vegetation may have prevented adequate ground capture. A newly requested area may fall outside the original collection limits. The project may require a measurement or verification that cannot be reliably obtained from the existing LiDAR data. Site conditions may also have changed since the original collection.
LiDAR should not be treated as a guarantee that nobody will ever need to return. Instead, it greatly increases the amount of information available from the original visit.
09
Better Planning Makes the Dataset More Useful
The best way to reduce future site visits is to think beyond the immediate deliverable before collecting data.
Project teams should consider which areas could become relevant later, what surfaces need to be visible, whether important structures or features are nearby, whether the project limits could expand, whether future volume calculations will be required, whether pre- and post-construction comparisons will be useful, and what accuracy is required.
A well-planned LiDAR collection can provide substantially more long-term value than a dataset collected without considering future needs.
- Which areas could become relevant later?
- What surfaces need to be visible?
- Are there important structures or features nearby?
- Could the project limits expand?
- Will future volume calculations be required?
- Will pre- and post-construction comparisons be useful?
- What accuracy is required?
